1. Field of the Invention
The present invention relates to methods, systems, and computer program products for communicating audio alerts to aircraft. More particularly, the present invention relates to methods, systems, and computer-program products for communicating auditory alerts regarding potential conflicts on arrival runways to approaching aircraft.
2. Background Art
The United States National Airspace System (NAS) comprises nearly 500 airports that collectively handle over 176,000 takeoffs on a daily basis. From 2001 to 2004, the Federal Aviation Administration reported that over 275 million flights passed through the NAS, rendering it the busiest air traffic management system in the world. During that same period, the FAA identified 1,395 runways incursions, resulting in a rate of 5.4 runway incursions per million flights.
The safe and efficient operation of the NAS stems from clear communication and smooth coordination between more than 15,000 air traffic controllers, 600,000 pilots, and thousands of airport vehicle operators that work within the NAS. In particular, the prevention of runway incursions depends upon the coordination between ground controllers, who are responsible for movement on the airport surface, local controllers, who verbally issue clearances for takeoffs and landings on the arrival and departure runways, and pilots, who respond to the instructions of local and ground controllers. However, given the increasing level of activity within the NAS, it may become difficult to maintain the clear communication and smooth coordination essential to the safe operation of aircraft within the NAS.
A number of automated alerting systems have been developed to supplement the close coordination between ground control, local control, and pilots. These automated systems often identify potential conflicts on the airport surface and then alert air traffic controllers to these potential conflicts who then in turn provide alerts to the cockpit. Other systems provide information to aircraft operating on airport surfaces, such as departure runways and taxiways, and to aircraft on final approach to arrival runways.
Unfortunately, a number of issues limit the wider adoption of these existing alerting systems within the NAS. In particular, systems that alert air traffic controllers about conflicts often delay the issuance of alerts to the cockpit. Systems that provide alerts directly to the cockpit require additional hardware and software that must be integrated into existing avionics systems on the aircraft.
Further, systems that do leverage existing receiver technologies, such as marker beacon receivers aboard aircraft within the NAS, function only on airport surfaces, and are often restricted to transmitting messages to aircraft from distances on the order of several feet. These systems are therefore inadequate to transmit advisory messages, cautions, and warnings concerning potential conflicts to aircraft approaching arrival runways from distances greater than a nautical mile. The term advisories as used here refers to situation awareness enhancing information. The term caution as used here refers to information that may require subsequent action from the flight crew. The term warning as used here refers to information requiring immediate subsequent action from the flight crew.